Hydraulic starter



A118 13, 1957 H. HOGEMAN HYDRAULIC .STARTER 2 Sheets-Sheet i Filed Oct. 20, 1953 zjnou utwzuw ZoFu/NTUDGNOG @z mmw UDGNOC m wQQ.

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INVENTR. HANS 'HOGE MAN ATTO/PNE All@ 13, l957 H. HQGEMAN 2,802,452

HYDRAULIC STARTER Filed Oct. 20, 1953 2 sheets-sheet 2 BLEED LINE To RESERVOIR a y om FROM ACCUMULATOE 27 "s ,29 A2f,

17 46 45 n 1' /D//V NEUTRAL 0E. aww/NG POS/T/o/v F'Yg. Z

23 (STARHNG VALVE) OIL RETURN To RESERVOIR On. mLET FROM ACCUMULATOE l la I9 (BELL CEAN'K) zo |84 I Q l l |1(CAM 120D) I5 \3(CAM 12ms) v MAX. ECCENTEICWV I4 4 -\o(\/ANE MOTO12)`- JNVENTOR.

HANS HOGEMAN 2,802,452 HYDRAULIC STARTER Hans Hogeman, Longmeadow, Mass., assigner to American Bosch Arma Corporation, a corperratum of New `York Application October 20, 1953, Serial No. 387,255

6 Claims. (Cl. 121-37) This invention relates to hydraulic motors and engine starters embodying such motors and has particular reference to a control for a variable displacement hydraulic motor adapted to be operatively connected to a load with the torque requirement of the motor being automatically controlled in relation to the torque requirements of the load, and also to an engine starter which embodies such a hydraulic motor and control as a power source and wherein the displacement of the motor is directly proportional to the ltorque required therefrom. p

. A` principal object of the invention is to provide means for automatically controlling the displacementA of a variable displacement hydraulic motor whereby the displacement :of said motor will be in accordance with load requirements. K Another object of the invention is to provide a new and improved hydraulic starter for internal combustion engines wherein theA starting motor produces the necessary torque required during the starting of the engine and wherein the torque provided at other times is reduced to a minimum.

Another object is to provide a hydraulic starter of the type set forth wherein the motor is self-regulating.

Another object is to provide a hydraulic starter employing a variable displacement motor as the power source thereof and wherein maximum torque will be provided during the actual starting of the engine and minimum ICC ring 13 for controlling the displacement of cam ring 13 and thereby controlling the power output of the motor.

Cam rod 17 is connected through the bell-crank 19 to cam rod actuator 20 which is connected to the` torque- 'reaction sensitive coupling 21 at 22. y

`Interposed in the oil or iluid inlet linev 11 from the accumulator is a starting valve 23 which comprises a housing 24 having a bore or chamber 25 in which is positioned a valve member 26 which is connected to starting valve lever 27 through valve stem or shaft 28. Valve 26 is retained in operative position by valve spring 29 in chamber 25.l

Bleed line 30 communicates with chamber 25 and the oil or tluid reservoir 31.

Starting mechanism is shown in Fig. 1, and includes the starting motor pinion 32 adapted to engage theV engine fly-wheel gear 33 when the pinion is advanced by the hydraulic starting motor against spring 34.

In the inside of a starter housing 35 is a piston 36 engaging pinion 32 or integral therewith, as shown, and adapted to function as hereinafter described. The torquereaction sensitive coupling 21 is provided with the torque spring 37 and in coupling 21 is also threaded the drive portion 38 which is keyed to vane motor 10 at 16, as previously described. Drivey member Y38 is adapted to be driven during the cranking cycle by the vane motor l() and returned in the opposite direction by high pressure lluid in chamber 39 which high pressure acts on piston 38a which passes into said chamber through port 40 from reservoir 31 which communicates with chamber l41 in pinion engaging piston 36 through port 42. v ,p A

The displacement of the Vane motor 10 is directly'jproportional to the torque required to crank the engine. As previously described, vane motor 10 has the adjustable eccentric cam ring 13, the eccentricity of which is changed by means of cam rod 17 which'is actuated by a torquereaction sensitive coupling.

torque provided at other times and wherein such motor will be self-regulating.

Other objects and advantages of the invention will be apparent from the following description taken in connection with the accompanying drawings. It will be understood that changes may be made in the details of construction and arrangement of parts Vshown and described as the preferred form has been given by way of illustration only.

Referring to the drawings: p

Fig. l is a diagrammatic View, partly in section, of a hydraulic starter embodying the invention;

Fig. 2 is a sectional view through the control valve arrangement; and

Fig. 3 is a sectional view through the motor and taken on line 3 3 of Fig. l, looking in the direction of the arrows.

Referring more particularly-to the drawings wherein similar reference characters designate corresponding parts throughout, the apparatus shown in Fig. 1 comprises the variable displacement motor 10 whichV is shown in the form of a vane motor which has an inlet 11 from a hydraulic fluid accumulator and an outlet or return 12 to a fluid reservoir.

The motor 10 is of the vane type, as stated, having the cam ring 13 within which is positioned the vanes 14 and drive shaft 15 which is keyed at 16 tothe starter drive mechanism.

The cam ring 13 of vane motor 10 nis controlled by cam rod 17 which extends into the housing of the vane motor and has the cam portion 18 adjustably engaging cam The vane motor 10 is driven by high pressure oil from an accumulator through starting valve 23. When the starting valve lever 27 is pulled out against spring 29 and turned from running position as shown in Fig. 2 into the starting'position, port 47 is aligned with the line from the accumulator to themotor as shown in Fig. l and high pressure oil. from` the accumulator is introduced momentarily to the torque coupling 21 and the pinion engaging piston 36 through the line from the accumulator and ports 49vand 49a, line 30, reservoir 31, and ports 40 and 42. This operation sets the cam ring 13 at maximum eccentricity and engages the starting motor `pinion 32 with the engine flywheel gear 33, allowing cranking of the engine immediately when the starting valve 23 reaches starting position.' In this starting position, the coupling shaft 38a .and pinion engaging piston 36 are relieved of high pressure oil through a bleed line back to the reservoir as hereinafter described. The coupling'shaft and engaging piston are now held in this position during the cranking cycle by the torque required to crank the engine. As the engine starts, and its cranking torque is reduced, the torque sensitive coupling starts returning the coupling shaft 38a into its chamber 39 by means of a torque spring. K

Valve 23 has the port 47 between spaced ports 49 and 49a and also has the track or cam slot `45 in which rides the pin 46 which controls the movement of the Valve and assures the feeding of oil through line 30.1501 starting and for bleeding when running. v v

As the shaft returns, it'moves the cam ring from maximum eccentricity, that is, the position of greatest torque to zero eccentricity which is the position of least torque through its connection to the cam rod actuator 20, bellcrank 19 and cam rod 17. At the sametime, the starting motor pinion 32 becomes disengaged by decreased torque 3; Y and is returned tol its running position (as shown in Fig. 1) by means' of compression spring 34'. As the engine starts, the operating or startling valve lever 27 is released andis returned toits running .position (shown in Eig. 2) b'yfa'.z return spjing actinclos'es olfhigh pres# oil tn vanefmot'or' 10 and the hydraulic starter is ar'lyforthe next start.`

When lever 27 is mov d fronineutral or running position, as ,shownindotted lines in Fig.' l, to starting position sXsh in; nur tiges in Eig. 1, ih'eiie fram .the accumul'atrx connected for an instant vvith line S'tl by vmeans if pero@ aad.49i. During this instant, pon 49l is nigiiea' within@ linarro'm the aceumiatr and port 49a is aligned vvit'liliney 30a`nd -dining this instant, uid passes fiirigh une su' t6 chamber 'Si from which it passes through port 42 tochamber 4l y,and acts upoupiston to forcev pinion 32 into engagement Withv gear 33 against the forqeofspringm ve 27 re .Ilul Huid passes' to the vane motor 1 0 yand spring 37 through hellerank v,19 andcam rod I17 positions cam ring 13 for displacement thereby giving maximum torque of 'ahsstjrfig podrian, the une from Ie vane. motor whichis coupled yto the starting drive shaft an drives .said shaft and thereby causes starting motor pinion'i to Vrotate and crank the' engine.

iVil'lieirtlie torque required to erank the engine is re# duced, the torque spring 37 adjusts the position of cam ring 13 toa position of less displacement through bell era'4 and cam rod17. This may occur after the rst cranking in otion'vvhich requires the greatest torque, as Welllas when the engine starts. Thislessens the supply high pressure fluid Vfrom the accumulator to the vane motor to that required by thctorque needed to crank the. engine,

After tlie engine has started, the lever 27 is moved from sta n'gpositionto running position which shuts on the supplypf fluid throu gh line 1 1 to the vane motor and s thenuid pressure in chamber l41'back through line to the bleed line and allovvs spring34 Vto move the ,pinion out of engagement vvith the engine ilywheel gear 3,3 f Y In Fig. 2- the startingyalve 23 and lever 27 are shown in neutral or rliljnin'g POSiOil.- I onLthe above it ill be seen that vane 'motor l0 is c rolledso as to provide povve'r only when needed and therefore, .the torque, employedto turn the engine uced to that required vvhich eliminates Waste of ,i aan rfrant ,it nu fbi?i seep that i unanimidad le eiieient. ande'conomitcl Ineens for obtaining all bjects and advantages of the invention.

'1. ni ,a ja vice; @fthe Charade; described@ variable displ ment hydranlicfmotor, means for varying the displacementof said motor, a pinion operatively connected to said motor, 4vsaid means yfor varying the displacement of lsaid motor including va torque sensitive coupling bei i said motor and said pinion, the load on the pinion actuatmg said `torque sensitive coupling and means operatively connecting said torque'sensitive coupling to said lmeans for varying the displacement lof saidmotor according, to theac'tuati'on of said torque sensitive coupling by said load on ysaid pinion.

2. In a device yof the character described, a variable displacement hydraulic'motor, means for varyingthe displa ementof said motor, a pinion operatively connected to said motor, said means for varying the displacement of s'ad motor including Ya torquesensitive coupling between said motor and said pinion, the loaden the pinion actuatin id torque sensitive coupling and means operatively connecting said torque sensitive coupling to said means is in communication with line 11Y and for varying the displacement of said motor according to the' actuation of said torque sensitive coupling' by' said load on said pinion, and hydraulic means for urging said pinion into operative position.

3. In a device of the character described, a variable displacement hydraulic motor, means for varying the displacement of said motor, -a pinion operatively connected to said motor, said means for varying Athe displacement of said motor including a torque sensitive coupling between said motor and said pinion, the load on the pinion actuating said torque sensitive coupling and means operatively connected said torque sensitive coupling to said means for varying the displacement of said motoraccording to the actuation of said torque sensitive coupling by said load on said pinion, and hydraulic means for urging said pinion into operative position, a hydraulicallyractuated piston operatively connected to said pinion and means whereby hydraulic force on said piston will actuate said pinion into operative position.

diailcflt Hydraulic rito, msansqfof .varying the. ,die placement ofv said in otor, a pinion operatively connected to said n iotor,l said means for varying the displacement of said motor including a torque sensitive coupling between said niotor and said pinion, the loadmonthe pinionactuat: ingV said torque sensitive coupling and means operatively connecting said torque sensitive coupling to said means for varying the displacement of saidniotor according to the actuation of said torque Vsensitive coupling said load on said pinion, said means operativelyconnecting said torque `sensitive coupling to Vsaid means for varying the displacement of said motor comprising cam means and means for actuating said cam means.

. 5)., In device of .the characterdesoribe'd, a variable displacement hydraulic motor, means for varying the displacement of said motor, a pinion operatively connected to saidrnotor, said means for varying the displacement of said motor including a torque sensitive coupling'betvveen saidmotorand s aid pinion,l the load on the pinion actuating V torque sensitive coupling and means operatively connectigb Said torque sensitive coupling to'A said means for varying the V,displacernent of saidmotor according to thefactuationof said torquef sensitive coupling said loadon said pinion, said torque V'sensitive coupling cornprising resilient means 'so arranged that the resilieiiey of said resilient means is a function of the torque applied onsaidpinion. 6 In^a 'e vi ce `o f thecharacter described, a variable disllrnent hydraulic motor, means for varying the displacement of said motor, a pinion operatively connected to said. motor, said means forv varying the displacement of `said motor including a torque sensitive coupling hetvveen said motor and saidV pinion, the load on the pinion actuating said torque sensitive coupling and means operatively connecting said torque sensitive coupling to said means for varyingtlev displacement of said motor aceording: to theactuation of said torque sensitive conplingby said load on said pinion, said torque 'sensitive coupling comprising a wound vspring so arranged rthat the tension ofsaid spring is a function of the torque applied on said pinion. Y

ReierencesjCited in tliele 'of patent UNITED vSTATES PATENTS 

